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tir33d

My LS1 280zx conversion

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Mentioned my plan a few weeks ago on here and now things are happening. Wallet and bank account on a manic decline.

The plan was to do a conversion for under $5000 and just have something to flog the hell out of on trackdays and club duties, well the $5000 has just gone past $10000 and I think I still have a couple of grand to go.

The plan is to have this running by the 13th August for a track day at Wakefield, currently I think I am still looking good. Looking for 400hp at the treads, reasonable size cam, 6 speed gearbox from VE commodore, CIG locked R200, hilux brakes (for now), fully stripped interior (including air con, heater box etc) half cage (but will probably weld some front legs also).

A friend of mine is helping me with the fabrication of the mounts and although a little tight, it looks like it was meant to be there. He does V6 conversions so has some of his own ideas. The motor mount uses the old aussie holden V8 mount, hers a photo while still in process.

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[/ihttp://i1011.photobucket.com/albums/af236/tir33d1/DSC01180.jpgmg]

 

Currently have the motor mounts done, gearbox mounts tomorrow and hopefully finish fuel system. New clutch slave necessary as the stock one - facing the motor is going to be too close. Going to have to run a new throttle cable.

Really enjoying having a project happening, although I now cannot tell the wife about any more purchases as I am not in the good books.

It is kind of a shame I made this a track car as it would be a hell of alot of fun on the road.

I will try to keep you all updated.

 

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Nice....looking good, keen to see how this turns out,

 

How's the tunnel clearance on the 6 spd from the VE?

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Which clutch master cylinder are you going to use?

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What do you mean about the clutch slave clearance? Isn't it inside the bellhousing. Or do you mean the master.

 

So you have 5.7L LS1 bolted to a VE 6 speed. What are the differences between gearboxes across the models. And what model car is the LS1 from.

Is your LS1 an LS1/LS6 etc, the early ones have a different inlet manifold which robs a few horse power. You can pick up LS6 manifolds fairly cheap to swap them over. That's something I'll have to do with mine.

 

Good to see the engine is as far back as possible in the bay, the shifter should line up sweet.

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Sorry your right, its the master that needs replacing. The difference between the VE box and earlier models is a slightly shorter input shaft and a slightly better gear set. I searched ebay for over 2 months hoping to get a T56 for around $1200. Every box that I bid on ended up going around $1500. In the end I got a brand new 6 speed for $2000. So I put the new box, along with a new textralia Z grip in my VE ute and pulled the old z grip out to use in the 280zx.

The main issue to be addressed with the shorter shaft is to ensure you have a bearing right at the end of the crank as the shaft only enters the bearing by about 10mm. Also the VE slave cylinder has shown to be a weak link in the commodore so a little tweaking and you change it to a VY style slave cylinder. This has been done in both my ute and the datsun.

As for the manifold I plan on replacing eventually with a single plane and decent throttle body on top similar to a four barrel. The cam 227/234 @ 112 with .640 intake lift and .595 exhaust should wake this old motor up nicely. The motor actually has over 200000kms on it but was run down the strip just prior to removal from a VX commodore (with a lot smaller cam it still managed 11.7.)

An idea on costs -

initial motor  -  swapped for $1000 worth of tyres

gearbox - $2000 + $200 shipping from adelaide

cam, springs, new oil pump, timing chain - $1500

2nd motor - bought for all ancillary parts and sensors - $1000

coilovers - (more on that one later >> tried to get some K-sports as they now list a part no but arrived on Friday and they didn't have adjustable tops and the rears are wrong) - $2000

clutch - $1200

shifter mechanism - $300

oil pan and remote fitting - $780

computer loom strip down and rewire - @$600

Still need to get some injectors and a tune on the motor - @$1000

 

+

+

Lots of bits also here and there but as you can see, even doing it cheap gets bloody expensive.

Looking back over those photos I think the first job today might be to clean up that engine bay a little.

 

 

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sure is amazing how the costs of a conversion add up looks cheap when u look at motor and box just everything else u need to make it work that adds up

not for the faint hearted lol and ive done it twice

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Two weeks later and I missed my deadline. My plan was to be running and using it at Wakefield yesterday but missed out by about a day.

Still not running just yet as we have changed tack on the fuel system. Exhaust also needs to be finished from the collector back.

This was the clearance issue at the master cylinder for the clutch - you will see the fix in a sec.

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Straightened the original fuel lines and re-run them across the firewall, the fuel system uses the original pump from the rear to pump up to a surge can at the front in the battery area.

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someone asked about tunnel clearance -

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my gearbox cam back a little further than planned, need to give myself an extra inch or so

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The magic master cylinder fix - a pedal lever system from a hyundai mounted so as to leave the master inside the cabin. You can also see my attempt at strengthening the dash area

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One of the spacers / plates made for the tailshaft mount - this tailshaft now has replacable uni's.

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Gearbox mount with tailshaft loop incorporated into it.

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Motor in and almost ready to go - radiator from a HZ holden with outlets moved to suit.

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Amate of mines first attempt at making extractors - I think he did a great job.

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I need to clean up some wires but the finished dash. Isolator, main ign switch, switch for second fuel pump (after catch can) start button. What else do you need?

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My rollcage - performed at an earlier date.

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Heres so bits I removed earlier LOL

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Hopefully tomorrow I will get a video file of the motor going!

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Wow, great progress.

That transmission mount looks like a trick bit of gear.

Make sure you bleed the clutch well before the last install. And either install a remote bleed for the clutch or cut a small hole in the trans tunnel for doing so as there isn't much room. Did you consider running a GM T56 clutch master with the remote fluid resoviour? They are quite small and would give you a bit more clearance. Speaking of which, how are you going to get to the cam sensor, oil pressure sensor and map sensor which are all at the rear of the inlet manifold?? There doesn't seem to be any room at all to get your hands down there which will become a real pain come wiring time. Although you did say you would be changing the manifold later.

And those headers, I don't think upgrading the cam will do you any good with such a small exhaust. The primaries look like they step down into 2". That's smaller than the factory cast ones. It might sound better but won't give you any more power. And if the cam and springs aren't in yet, I'd get the better springs in before taking it for a lap as you know how weak they are.

As you're going to be racing it I would seriously recommend getting a big rocker cover breather system too. An old tired LS1 will like to 'breathe' a lot and the factory set up is very restrictive.

Whats are your plans with the fuel system after it gets to surge tank in the engine bay (pump, reg, return etc).

Good luck with the wiring etc. I have some great colour pdf wiring diagrams for the LS1 if you need em.

cheers

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I had the local clutch joint make me a bleed line about 8 inches long which hangs ourside the box for bleeding as I know that even on my VE ute that its a pain - oh and they made it in braided line (just to take more money out of my wallet). That master is actually a $30 unit. I have a limited pool of knowledge to tap where I live and was advised that a shorter cylinder was unavailable by the local supplier),

As for the sensors they are all connected bar the oil pressure - this was left off by Steve at Killa's as he knew it was a track only jobbie and I was going to run mechanical gauges. And although tight down there I can still disconnect wiring if necessary.

As for the exhaust they are 1 5/8 primary to a 2 1/2 four into one which we are going to meet together prir to the diff to 3 inch for a single muffler at rear. I would have liked 1 3/4 primary but space was very tight on drivers side. Notice how we had to mount one coil pack ontop of the other for clearance even on top. I really should have cleaned the welds up a little to make them look better but they are a really good job.

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The cam is in already, and we have installed PAC extreme springs for safe 7000rpm running. I'm a little anal about the spring thing also (just replaced my springs in my ute for the second time in 65000kms)

The fuel system has a pump in the original location which I thought initially was a 044 bosch, have since figured it to be a smaller unit but it was still up to the task of feeding the previous turbo 6. Feeds to a swirlpot on old battery tray, out of surge to 044 bosch, non return valve into 8mm to standard fuel rail, ends removed from rail at firewall and joined via a malpassi regulator, purge to surge tank. Hopefully this will work, we did try today to do a basic deadhead system with old style mechanical reg after 044, mmmm lets say that we changed plans after that.

Thanks for the offer of the wiring but hopefully it should all go, I had Killa's do the kit and wire it so it only has what is necessary.

So looking forward to driving this thing.........

Phil

 

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Well, my poor little dato has been fighting me all week. Little jobs turn into half day marathons, and worst of all little hiccups have held me up also. One major hiccup was in the form of no oil pressure in the motor. After priming the oil system several times and in several different ways we came to the conclusion that we must have had an issue at the sump pickup. So rather than pulling out the motor and box (and exhaust wiring loom, clutch slave, radiator etc) we dropped the crossmember with the motor supported on the towers. Upon inspection I found that I had pinched the oring on installation of the pickup.

So back together again, then about to move off the hoist and I noticed that the master for the clutch was loosing some fluid with each clutch stroke. MMMM. Box out again, found that bleed line I had made wasn't tightened enough so was leaking. back together again.

Anyway, oil pressure good, clutch pressure good. Motor starts and idles roughly as the cam is feeding way too much fuel. Booked in for a tune on Monday morning 9am in Sydney, then I might try to convince the wife to let me go to Wakefield on Wednesday for a day of sorting. Then on Sunday 29th we have a Hillclimb here at Bathurst.

Hopefully I will take some more photos tomorrow. I will also try to get a little video of the dyno on Monday.

With the current tune and cam it sounds like a full on stockcar, I know the tune will calm it down a little, but I hope the sound still stays, it sound so horny I tell ya!

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in same boat with my car since fitting big cam its running very rich and lumpy but wow that cam really opens the engine up

what sort exhaust have you fitted to your car running cats and twin 2.5" on mine with resonator on each bank and single straight through muffler at rear before cam was thinking a little quiet but since cam think it be best left alone

 

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LOL I have 1 5/8 primary 2.5 twins to diff then into a single 3 inch edelbrock rear muffler. It does a bit, but not much. I had a pair of 600mm hotdogs/resonators but we decided to leave them off.

Lucky you didn't change your exhaust before your cam. Even my ute sounds heaps crankier and louder with the cam. How big is your cam, has it been tuned, how much power and most importantly how is your diff (I assume you have a R200)

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i went with 1 7/8 primary pipes cam is c.o.m.e racing one when i rang sam at c.o.m.e he says what you want cam for told him ls1 in 240z and he says your insane why do u want a cam for that must be an animal std lol then says well since your crazy go with 232 in 242 exh as big as he would recommend without major internal changes

Had mafless tune done before i installed std motor organising tune for cam shortly still deciding whether to bottle NOZ bottle on when i get tune done see what it makes with extra squirt

Diff is working fine running Dr30 skyline clutched r200

cam comes on like a 2 stroke power band at 3000 rpm then just pulls like a train till redline

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Great news that its running now. Lucky pick up on both the clutch and the oil pressure. Definetly looking foward to a vid to hear the cammed angriness. Has it driven under chev power yet.

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Well the motor is still intact. And I have seen and heard it run at 7000rpm. Now the tuner and my mechanic mate from Syd way are a little dissapointed at the number but I really don't care as I didn't build it as a dyno queen.They seem to think my little short mainfolds are not helping but I kind of new that. As long as it is strong and revs well I will be happy.

Now my tuner has set a resonable tune, but I am not running oxygen sensors in the exhaust and he didn't have his wideband so was only using a probe up the butt. I have in the car now a scanner and wide ban to log some figures at Wakefield and he will then adjust to suit.

Now remember that the tuner and mechanic are used to seeing big numbers so 350hp or 260kw was a little sad for them. But franky its at least twice as powerfull as before and probably three times. If like my commodore I had 1 7/8 extractors with more eual lungth runners and twin 2.5 inch all the way there is prob another 15-20kw. Anyway still hoping to get away on Wednesday to Wakefield for a practice before the hillclimb.

 

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At least 260rwkw is up in the cammed ls1 levels, past the bolt on only levels. See how those headers perform on the track and change them later. Quick question since you mention a lack of u2 sensors, are you running an inlet air temp sensor?

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did you get it idling smooth with tune

Im sure you will have a ball with 350 hp when i put my car together i was having lot of fun with it running on 7 cylinders showed 247 hp on dyno (one plug shorted out to extractor) was very exciting when i fixed that and had 295 hp

cant wait to see what dyno shows now with cam cause it pulls so much harder now sam at c.o.m.e reckoned cam be good for extra 100hp at wheels

have great time on the track with car

 

mick

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That was me on the dyno.

Went to Wakefield today and managed a string of 1.11's. Will post a incar vid later.

Definitely need brakes, a power steer cooler, and need to cover up some holes in the firewall as my eyes are still sore from the fumes.

Was funny, I was thrown in with the Tin Top racers. All pro cars really and I held my own against all of them. My cheap little dato.....

 

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Had our hillclimb today, heres a bit of real noise. I took a mate with me and we double entered the car. That will explain why one run is controlled then the next is out there.

Had a great day, I think I love my Z.

 

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I know its worthless without photos but, the exhaust has finally been redone to mamoth proportions. For some reason every exhaust shop I rang near where I live didn't want the job "oh that will be costly" - so what I know what I want.

Windsor exhaust in Sydney just finished today a set of custom 1 7/8 long tube primary to a race merge 4 into 1. Runs clean down the tunnel through dual 3 inch to a single muffler with dual 3 inch in and dual 3 inch out. Dumps just in front of the diff. The sound is tremendous. Prob a touch noisy but it is a track car only so not to worried. The drivers side proved to be the issue as before, but they basically made 4 individual pipes with unfortunately one longer pipe by about 3 inches due to space.

Really happy with the workmanship and the ground clearance. Price -- wait for it -- $2500. I knew it would be that much yet the local blokes still didn't want to have a go. Bunch of tossers.

Now in the next week or so we are going to re-do the fuel system so I am not pumping so much fuel so far, removing the large pump from the rear and installing a lift pump instead - feeding to the swirlpot which we are going to mount in the spare tyre area and enclose with prob a flute to atmosphere to prevent fuming in cab. Run some bigger lines up to the front and install a 92mm fast throttle body and fast manifold ($1200 second hand).

Then we are going to rebuild the cage to full CAM specs.

Running out of time as I know the cage will be time consuming this time (not the 3 or so hours from last time) I want it running for end of Feb as we have a double hillclimb at Bathurst SS's on Sat and Mountain straight on Sunday.

Oh how my wife luvs my hobby..............

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